Update dataspace patterns protocol

Skeletons do not check for the presence of ignored entries in
pattern matches, this will cause bugs!

src/syndicate.nim

@@ -19,7 +19,7 @@ proc `!`*(typ: static typedesc): Pattern {.inline.} =
   patterns.dropType(typ)
 
 proc `?`*[T](val: T): Pattern {.inline.} =
-  patterns.grab[T](val)
+  patterns.drop[T](val)
 
 proc `?:`*(typ: static typedesc): Pattern {.inline.} =
   patterns.grabType(typ)
@@ -30,9 +30,6 @@ proc `?:`*(typ: static typedesc; bindings: sink openArray[(int, Pattern)]): Patt
 proc `?:`*(typ: static typedesc; bindings: sink openArray[(Value, Pattern)]): Pattern {.inline.} =
   patterns.grab(typ, bindings)
 
-proc `??`*(pat: Pattern; bindings: openArray[(int, Pattern)]): Pattern {.inline.} =
-  patterns.inject(pat, bindings)
-
 type
   PublishProc = proc (turn: var Turn; v: Value; h: Handle) {.closure.}
   RetractProc = proc (turn: var Turn; h: Handle) {.closure.}

src/syndicate/Tupfile

@@ -1,3 +1,4 @@
 include_rules
 NIM_FLAGS += --path:$(TUP_CWD)/..
 : foreach *.nim |> !nim_check |>
+: patterns.nim |> !nim_bin |>

src/syndicate/drivers/http_driver.nim

@@ -16,8 +16,6 @@ when defined(posix):
   proc echo(args: varargs[string, `$`]) {.used.} =
     stderr.writeLine(args)
 
-proc `$`(b: seq[byte]): string = cast[string](b)
-
 proc badRequest(conn: Connection; msg: string) =
   conn.send(SupportedVersion & " 400 " & msg, endOfMessage = true)
 
@@ -33,6 +31,9 @@ proc extractQuery(s: var string): Table[Symbol, seq[QueryValue]] =
 
 proc parseRequest(conn: Connection; text: string): (int, HttpRequest) =
   ## Parse an `HttpRequest` request out of a `text` from a `Connection`.
+  result[1].host = RequestHost(orKind: RequestHostKind.absent)
+  result[1].body = RequestBody(orKind: RequestBodyKind.absent)
+
   var
     token: string
     off: int
@@ -91,13 +92,13 @@ proc parseRequest(conn: Connection; text: string): (int, HttpRequest) =
     for e in vals.mitems:
       e = e.toLowerAscii
       if k == Symbol"host":
-        result[1].host = e
+        result[1].host = RequestHost(orKind: RequestHostKind.`present`, present: e)
       if v == "": v = move e
       else:
         v.add ", "
         v.add e
       if k == Symbol"host":
-        result[1].host = v
+        result[1].host = RequestHost(orKind: RequestHostKind.`present`, present: v)
       result[1].headers[k] = v
 
   result[0] = off
@@ -140,6 +141,9 @@ proc send(ses: Session; chunk: Chunk) =
   of ChunkKind.bytes:
     ses.send(chunk.bytes)
 
+func `==`(s: string; rh: RequestHost): bool =
+  rh.orKind == RequestHostKind.present and rh.present == s
+
 proc match(b: HttpBinding, r: HttpRequest): bool =
   ## Check if `HttpBinding` `b` matches `HttpRequest` `r`.
   result =
@@ -241,9 +245,8 @@ proc service(turn: var Turn; exch: Exchange) =
     if handler.isNone:
       stop(turn)
     else:
-      let
-        cap =  newCap(turn, exch)
-        ctx = publish(turn, handler.get, HttpContext(
+      let cap =  newCap(turn, exch)
+      publish(turn, handler.get, HttpContext(
           req: exch.req,
           res: embed cap,
         ))

src/syndicate/drivers/timers.nim

@@ -1,9 +1,9 @@
 # SPDX-FileCopyrightText: ☭ Emery Hemingway
 # SPDX-License-Identifier: Unlicense
 
-import std/times
+import std/[tables, times]
 import preserves
-import ../../syndicate, ../bags, ../protocols/[timer, dataspace]
+import ../../syndicate, ../protocols/[timer, dataspace]
 
 when defined(solo5):
   import solo5_dispatcher
@@ -27,7 +27,7 @@ when defined(solo5):
         ## Owning facet of driver.
       target: Cap
         ## Destination for LaterThan assertions.
-      deadlines: Bag[float]
+      deadlines: Table[float, Facet]
         ## Deadlines that other actors are observing.
 
   proc spawnTimerDriver(facet: Facet; cap: Cap): TimerDriver =
@@ -35,11 +35,12 @@ when defined(solo5):
 
   proc await(driver: TimerDriver; deadline: float) {.solo5dispatch.} =
     yieldUntil(deadline)
-    if deadline in driver.deadlines:
+    let facet = driver.deadlines.getOrDefault(deadline)
+    if not facet.isNil:
       # check if the deadline is still observed
       proc turnWork(turn: var Turn) =
         discard publish(turn, driver.target, LaterThan(seconds: deadline))
-      run(driver.facet, turnWork)
+      run(facet, turnWork)
 
 else:
   import std/[oserrors, posix, sets]
@@ -84,7 +85,7 @@ else:
         ## Owning facet of driver.
       target: Cap
         ## Destination for LaterThan assertions.
-      deadlines: Bag[float]
+      deadlines: Table[float, Facet]
         ## Deadlines that other actors are observing.
       timers: HashSet[cint]
         # TODO: use a single timer descriptor
@@ -100,7 +101,7 @@ else:
   proc earliestFloat(driver: TimerDriver): float =
     assert driver.deadlines.len > 0
     result = high float
-    for deadline in driver.deadlines:
+    for deadline in driver.deadlines.keys:
       if deadline < result:
         result = deadline
 
@@ -119,11 +120,12 @@ else:
       # Check if the timer is expired which
       # could happen before waiting.
       wait(FD fd, Read)
-    if deadline in driver.deadlines:
+    let facet = driver.deadlines.getOrDefault(deadline)
+    if not facet.isNil:
       # Check if the deadline is still observed.
       proc turnWork(turn: var Turn) =
         discard publish(turn, driver.target, LaterThan(seconds: deadline))
-      run(driver.facet, turnWork)
+      run(facet, turnWork)
     discard close(fd)
     driver.timers.excl(fd)
 
@@ -132,16 +134,15 @@ proc spawnTimerDriver*(turn: var Turn; ds: Cap): Actor {.discardable.} =
   ## dataspace observations of timeouts on `ds`.
   linkActor(turn, "timers") do (turn: var Turn):
     let driver = spawnTimerDriver(turn.facet, ds)
-    let pat = inject(grab Observe(pattern: dropType LaterThan), {0: grabLit()})
+    let pat = observePattern(!LaterThan, {@[0.toPreserves]: grabLit()})
     during(turn, ds, pat) do (deadline: float):
-      if change(driver.deadlines, deadline, +1) == cdAbsentToPresent:
-        discard trampoline(whelp await(driver, deadline))
+      driver.deadlines[deadline] = turn.facet
+      discard trampoline(whelp await(driver, deadline))
     do:
-      discard change(driver.deadlines, deadline, -1, clamp = true)
-        # TODO: retract assertions that are unobserved.
+      driver.deadlines.del deadline
 
 proc after*(turn: var Turn; ds: Cap; dur: Duration; act: TurnAction) =
   ## Execute `act` after some duration of time.
   var later = wallFloat() + dur.inMilliseconds.float / 1_000.0
-  onPublish(turn, ds, grab LaterThan(seconds: later)):
+  onPublish(turn, ds, ?LaterThan(seconds: later)):
     act(turn)

src/syndicate/patterns.nim

@@ -1,70 +1,46 @@
 # SPDX-FileCopyrightText: ☭ Emery Hemingway
 # SPDX-License-Identifier: Unlicense
 
-import std/[algorithm, assertions, options, sequtils, tables, typetraits]
+import std/[assertions, options, tables, typetraits]
 
 import preserves
-import ./protocols/dataspacePatterns
+import ./protocols/[dataspacePatterns, dataspace]
 from ./actors import Cap
 
-export dataspacePatterns.`$`, PatternKind, DCompoundKind, AnyAtomKind
+export dataspacePatterns.`$`, AnyAtomKind, GroupTypeKind, PatternKind
 
 type
-  AnyAtom = dataspacePatterns.AnyAtom
-  DBind = dataspacePatterns.DBind
-  DCompound = dataspacePatterns.DCompound
-  DCompoundArr = dataspacePatterns.DCompoundArr
-  DCompoundDict = dataspacePatterns.DCompoundDict
-  DCompoundRec = dataspacePatterns.DCompoundRec
-  DLit = dataspacePatterns.DLit
   Pattern* = dataspacePatterns.Pattern
 
-iterator orderedEntries*(dict: DCompoundDict): (Value, Pattern) =
-  ## Iterate a `DCompoundDict` in Preserves order.
-  ## Values captured from a dictionary are represented as an
-  ## array of values ordered by their former key, so using an
-  ## ordered iterator is sometimes essential.
-  var keys = dict.entries.keys.toSeq
-  sort(keys, preserves.cmp)
-  for k in keys:
-    yield(k, dict.entries.getOrDefault(k))
-      # getOrDefault doesn't raise and we know the keys will match
+proc toPattern(b: sink PatternBind): Pattern =
+  Pattern(orKind: PatternKind.`bind`, `bind`: b)
 
-proc toPattern(d: sink DBind): Pattern =
-  Pattern(orKind: PatternKind.DBind, dbind: d)
+proc toPattern(l: sink PatternLit): Pattern =
+  Pattern(orKind: PatternKind.`lit`, lit: l)
 
-proc toPattern(d: sink DLit): Pattern =
-  Pattern(orKind: PatternKind.DLit, dlit: d)
+proc toPattern(g: sink PatternGroup): Pattern =
+  Pattern(orKind: PatternKind.`group`, group: g)
 
-proc toPattern(aa: sink AnyAtom): Pattern =
-  DLit(value: aa).toPattern
+proc toPattern(a: sink AnyAtom): Pattern =
+  PatternLit(value: a).toPattern
 
-proc toPattern(d: sink DCompound): Pattern =
-  Pattern(orKind: PatternKind.DCompound, dcompound: d)
+proc grab*(p: sink Pattern): Pattern =
+  PatternBind(pattern: p).toPattern
 
-proc toPattern(d: sink DCompoundRec): Pattern =
-  DCompound(orKind: DCompoundKind.rec, rec: d).toPattern
-
-proc toPattern(d: sink DCompoundArr): Pattern =
-  DCompound(orKind: DCompoundKind.arr, arr: d).toPattern
-
-proc toPattern(d: sink DCompoundDict): Pattern =
-  DCompound(orKind: DCompoundKind.dict, dict: d).toPattern
-
-proc drop*(): Pattern {.inline.} = Pattern(orKind: PatternKind.DDiscard)
+proc drop*(): Pattern = Pattern(orKind: PatternKind.`discard`)
   ## Create a pattern to match any value without capture.
 
-proc grab*(): Pattern {.inline.} = DBind(pattern: drop()).toPattern
+proc grab*(): Pattern = drop().grab()
   ## Create a pattern to capture any value.
 
-proc grab*(pr: Value): Pattern =
+proc drop*(pr: Value): Pattern =
   ## Convert a `Preserve` value to a `Pattern`.
   runnableExamples:
     from std/unittest import check
     import preserves
     check:
-      $(grab parsePreserves"""<foo "bar" #"00" [0 1 2.0] {maybe: #t} <_>>""") ==
-        """<rec foo [<lit "bar"> <lit #"00"> <arr [<lit 0> <lit 1> <lit 2.0>]> <dict {maybe: <lit #t>}> <_>]>"""
+      $("""<foo "bar" #"00" [0 1 2.0] {maybe: #t} <_>>""".parsePreserves.drop) ==
+        """<group <rec foo> {0: <lit "bar"> 1: <lit #"00"> 2: <group <arr> {0: <lit 0> 1: <lit 1> 2: <lit 2.0>}> 3: <group <dict> {maybe: <lit #t>}> 4: <_>}>"""
 
   case pr.kind
   of pkBoolean:
@@ -73,43 +49,65 @@ proc grab*(pr: Value): Pattern =
     AnyAtom(orKind: AnyAtomKind.`double`, double: pr.float).toPattern
   of pkRegister:
     AnyAtom(orKind: AnyAtomKind.`int`, int: pr.register).toPattern
+  of pkBigInt:
+    raiseAssert "cannot make a pattern over a big integer"
   of pkString:
     AnyAtom(orKind: AnyAtomKind.`string`, string: pr.string).toPattern
   of pkByteString:
     AnyAtom(orKind: AnyAtomKind.`bytes`, bytes: pr.bytes).toPattern
   of pkSymbol:
     AnyAtom(orKind: AnyAtomKind.`symbol`, symbol: pr.symbol).toPattern
+
   of pkRecord:
-    if (pr.isRecord("_") and pr.arity == 0) or (pr.isRecord("bind") and pr.arity == 1):
+    if pr.isRecord("_", 0):
       drop()
+    elif pr.isRecord("bind", 1):
+      pr.fields[0].drop
     else:
-      DCompoundRec(
-        label: pr.label,
-        fields: map[Value, Pattern](pr.fields, grab)).toPattern
+      var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.rec))
+      group.`type`.rec.label = pr.label
+      var i: int
+      for v in pr.fields:
+        group.entries[toPreserves i] = drop v
+        inc i
+      group.toPattern
+
   of pkSequence:
-    DCompoundArr(items: map(pr.sequence, grab)).toPattern
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.arr))
+    for i, v in pr.sequence:
+      group.entries[toPreserves i] = drop v
+    group.toPattern
+
   of pkSet:
     raiseAssert "cannot construct a pattern over a set literal"
+
   of pkDictionary:
-    var dict = DCompoundDict()
-    for key, val in pr.pairs: dict.entries[key] = grab val
-    dict.toPattern
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.dict))
+    for key, val in pr.pairs:
+      group.entries[key] = drop val
+    group.toPattern
+
   of pkEmbedded:
     if pr.embeddedRef.isNil: drop()
     else:
       AnyAtom(orKind: AnyAtomKind.`embedded`, embedded: pr.embeddedRef).toPattern
-  else:
-    raise newException(ValueError, "cannot generate a pattern for unhandled Value type")
+  #else:
+  #  raise newException(ValueError, "cannot generate a pattern for unhandled Value type")
 
-proc grab*[T](x: T): Pattern =
+proc drop*[T](x: T): Pattern =
   ## Construct a `Pattern` from value of type `T`.
+  ## This proc is called `drop` because the value `x` is matched but discarded.
   runnableExamples:
     from std/unittest import check
     check:
-      $grab(true) == "<lit #t>"
-      $grab(3.14) == "<lit 3.14>"
-      $grab([0, 1, 2, 3]) == "<arr [<lit 0> <lit 1> <lit 2> <lit 3>]>"
-  grab(x.toPreserves)
+      $drop(true) == "<lit #t>"
+      $drop(3.14) == "<lit 3.14>"
+      $drop([0, 1, 2, 3]) == "<group <arr> {0: <lit 0> 1: <lit 1> 2: <lit 2> 3: <lit 3>}>"
+  drop(x.toPreserves)
+
+proc grab*[T](x: T): Pattern {.
+    deprecated: "use drop unless you wish to capture the provided value".} =
+  PatternBind(pattern: drop x).toPattern
 
 proc grabType*(typ: static typedesc): Pattern =
   ## Derive a `Pattern` from type `typ`.
@@ -120,40 +118,41 @@ proc grabType*(typ: static typedesc): Pattern =
     from std/unittest import check
     check:
       $grabType(array[3, int]) ==
-        """<arr [<bind <_>> <bind <_>> <bind <_>>]>"""
+        """<group <arr> {0: <bind <_>> 1: <bind <_>> 2: <bind <_>> 3: <bind <_>>}>"""
     type
       Point = tuple[x: int; y: int]
       Rect {.preservesRecord: "rect".} = tuple[a: Point; B: Point]
       ColoredRect {.preservesDictionary.} = tuple[color: string; rect: Rect]
     check:
       $(grabType Point) ==
-        "<arr [<bind <_>> <bind <_>>]>"
+        "<group <arr> {0: <bind <_>> 1: <bind <_>>}>"
       $(grabType Rect) ==
-        "<rec rect [<arr [<bind <_>> <bind <_>>]> <arr [<bind <_>> <bind <_>>]>]>"
+        "<group <rec rect> {0: <group <arr> {0: <bind <_>> 1: <bind <_>>}> 1: <group <arr> {0: <bind <_>> 1: <bind <_>>}>}>"
       $(grabType ColoredRect) ==
-        "<dict {color: <bind <_>> rect: <rec rect [<arr [<bind <_>> <bind <_>>]> <arr [<bind <_>> <bind <_>>]>]>}>"
+        "<group <dict> {color: <bind <_>> rect: <group <rec rect> {0: <group <arr> {0: <bind <_>> 1: <bind <_>>}> 1: <group <arr> {0: <bind <_>> 1: <bind <_>>}>}>}>"
   when typ is ref:
     grabType(pointerBase(typ))
   elif typ.hasPreservesRecordPragma:
-    var rec = DCompoundRec(label: typ.recordLabel.toSymbol)
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`rec`))
+    group.`type`.rec.label = typ.recordLabel.toSymbol
     for _, f in fieldPairs(default typ):
-      add(rec.fields, grabType(typeof f))
-    result = rec.toPattern
+      group.entries[group.entries.len.toPreserves] = grabType(typeof f)
+    group.toPattern
   elif typ.hasPreservesDictionaryPragma:
-    var dict = DCompoundDict()
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`dict`))
     for key, val in fieldPairs(default typ):
-      dict.entries[key.toSymbol] = grabType(typeof val)
-    dict.toPattern
+      group.entries[key.toSymbol] = grabType(typeof val)
+    group.toPattern
   elif typ is tuple:
-    var arr = DCompoundArr()
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`arr`))
     for _, f in fieldPairs(default typ):
-      add(arr.items, grabType(typeof f))
-    arr.toPattern
+      group.entries[group.entries.len.toPreserves] = grabType(typeof f)
+    group.toPattern
   elif typ is array:
-    var arr = DCompoundArr()
-    arr.items.setLen(len(typ))
-    for e in arr.items.mitems: e = grab()
-    arr.toPattern
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`arr`))
+    for i in 0..len(typ):
+      group.entries[toPreserves i] = grab()
+    group.toPattern
   else:
     grab()
 
@@ -166,59 +165,47 @@ proc dropType*(typ: static typedesc): Pattern =
   when typ is ref:
     dropType(pointerBase(typ))
   elif typ.hasPreservesRecordPragma:
-    var rec = DCompoundRec(label: typ.recordLabel.toSymbol)
-    rec.fields.setLen(fieldCount typ)
-    for i, _ in rec.fields:
-      rec.fields[i] = drop()
-    result = rec.toPattern
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`rec`))
+    group.`type`.rec.label = typ.recordLabel.toSymbol
+    let high = typ.fieldCount.pred
+    if high >= 0: group.entries[high.toPreserves] = drop()
+    group.toPattern
   elif typ.hasPreservesDictionaryPragma:
-    DCompoundDict().toPattern
-  elif typ is tuple:
-    var arr = DCompoundArr()
-    arr.items.setLen(len typ)
-    for i, _ in arr.items:
-      arr.items[i] = drop()
-    arr.toPattern
-  elif typ is array:
-    var arr = DCompoundArr()
-    arr.items.setLen(len(typ))
-    for e in arr.items.mitems: e = drop()
-    arr.toPattern
+    PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`dict`)).toPattern
+  elif typ is tuple or typ is array:
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`arr`))
+    let high = typ.fieldCount.pred
+    if high >= 0: group.entries[high.toPreserves] = drop()
+    group.toPattern
   else:
     drop()
 
-proc lookup(bindings: openArray[(int, Pattern)]; i: int): Pattern =
-  for (j, b) in bindings:
-    if i == j: return b
-  return drop()
+proc bindEntries(group: var PatternGroup; bindings: openArray[(int, Pattern)]) =
+  ## Set `bindings` for a `group`.
+  for (i, pat) in bindings: group.entries[toPreserves i] = pat
 
 proc grab*(typ: static typedesc; bindings: sink openArray[(int, Pattern)]): Pattern =
   ## Construct a `Pattern` from type `typ` with pattern `bindings` by integer offset.
   when typ is ptr | ref:
     grab(pointerBase(typ), bindings)
   elif typ.hasPreservesRecordPragma:
-    var rec = DCompoundRec(label: typ.recordLabel.toSymbol)
-    rec.fields.setLen(fieldCount typ)
-    var i: int
-    for _, f in fieldPairs(default typ):
-      rec.fields[i] = lookup(bindings, i)
-      inc i
-    result = rec.toPattern
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`rec`))
+    group.`type`.rec.label = typ.recordLabel.toSymbol
+    bindEntries(group, bindings)
+    group.toPattern
   elif typ is tuple:
-    var arr = DCompoundArr()
-    arr.items.setLen(fieldCount typ)
-    var i: int
-    for _, f in fieldPairs(default typ):
-      arr.items[i] = lookup(bindings, i)
-      inc i
-    result = arr.toPattern
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`arr`))
+    bindEntries(group, bindings)
+    group.toPattern
   else:
     {.error: "grab with indexed bindings not implemented for " & $typ.}
 
 proc grab*(typ: static typedesc; bindings: sink openArray[(Value, Pattern)]): Pattern =
   ## Construct a `Pattern` from type `typ` with dictionary field `bindings`.
   when typ.hasPreservesDictionaryPragma:
-    DCompoundDict(entries: bindings.toTable).toPattern
+    var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`dict`))
+    for key, val in bindinds: group.entries[key] = val
+    group.toPattern
   else:
     {.error: "grab with dictionary bindings not implemented for " & $typ.}
 
@@ -226,11 +213,11 @@ proc grabLit*(): Pattern =
   runnableExamples:
     from std/unittest import check
     check:
-      $grabLit() == """<rec lit [<bind <_>>]>"""
-  grabType(dataspacePatterns.DLit)
+      $grabLit() == """<group <rec lit> {0: <bind <_>>}>"""
+  grabType(dataspacePatterns.PatternLit)
 
 proc grabDict*(): Pattern =
-  grabType(dataspacePatterns.DCompoundDict)
+  grabType(dataspacePatterns.GroupTypeDict)
 
 proc unpackLiterals*(pr: Value): Value =
   result = pr
@@ -238,64 +225,42 @@ proc unpackLiterals*(pr: Value): Value =
     if pr.isRecord("lit", 1) or pr.isRecord("dict", 1) or pr.isRecord("arr", 1) or pr.isRecord("set", 1):
       pr = pr.record[0]
 
-proc inject*(pat: Pattern; bindings: openArray[(int, Pattern)]): Pattern =
-  ## Construct a `Pattern` from `pat` with injected overrides from `bindings`.
+proc inject*(pattern: sink Pattern; p: Pattern; path: varargs[Value, toPreserves]): Pattern =
+  ## Inject `p` inside `pattern` at `path`.
   ## Injects are made at offsets indexed by the discard (`<_>`) patterns in `pat`.
-  proc inject(pat: Pattern; bindings: openArray[(int, Pattern)]; offset: var int): Pattern =
-    case pat.orKind
-    of PatternKind.DDiscard:
-      result = pat
-      for (off, injection) in bindings:
-        if off == offset:
-          result = injection
-          break
-      inc offset
-    of PatternKind.DBind:
-      let bindOff = offset
-      result = pat
-      result.dbind.pattern = inject(pat.dbind.pattern, bindings, offset)
-      if result.orKind == PatternKind.DBind:
-        for (off, injection) in bindings:
-          if (off == bindOff) and (result.dbind.pattern == injection):
-            result = result.dbind.pattern
-            break # promote the injected pattern over the bind
-    of PatternKind.DLit:
-      result = pat
-    of PatternKind.DCompound:
-      result = pat
-      case pat.dcompound.orKind
-      of DCompoundKind.rec:
-        var fields = mapIt(pat.dcompound.rec.fields):
-          inject(it, bindings, offset)
-        result = DCompoundRec(label: result.dcompound.rec.label, fields: fields).toPattern
-      of DCompoundKind.arr:
-        var items = mapIt(pat.dcompound.arr.items):
-          inject(it, bindings, offset)
-        result = DCompoundArr(items: items).toPattern
-      of DCompoundKind.dict:
-        var dict = DCompoundDict()
-        for key, val in pat.dcompound.dict.entries:
-          dict.entries[key] = inject(val, bindings, offset)
-        result = toPattern(dict)
-  var offset = 0
-  inject(pat, bindings, offset)
-
-proc inject*(pat: Pattern; bindings: openArray[(Value, Pattern)]): Pattern =
-  ## Inject `bindings` into a dictionary pattern.
-  assert pat.orKind == PatternKind.DCompound
-  assert pat.dcompound.orKind == DCompoundKind.dict
-  result = pat
-  for (key, val) in bindings:
-    result.dcompound.dict.entries[key] = val
+  proc inject(pat: var Pattern; path: openarray[Value]) =
+    if len(path) == 0:
+      pat = p
+    elif pat.orKind != PatternKind.`group`:
+      raise newException(ValueError, "cannot inject along specified path")
+    else:
+      inject(pat.group.entries[path[0]], path[1..path.high])
+  result = pattern
+  inject(result, path)
 
 proc grabRecord*(label: Value, fields: varargs[Pattern]): Pattern =
   runnableExamples:
     from std/unittest import check
-    import syndicate/actors, preserves
+    import preserves
     check:
       $grabRecord("Says".toSymbol, grab(), grab()) ==
-        """<rec Says [<bind <_>> <bind <_>>]>"""
-  DCompoundRec(label: label, fields: fields.toSeq).toPattern
+        """<group <rec Says> {0: <bind <_>> 1: <bind <_>>}>"""
+  var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`rec`))
+  group.`type`.rec.label = label
+  for i, f in fields: group.entries[toPreserves i] = f
+  group.toPattern
+
+proc grabRecord*(label: Value, fields: sink openArray[(int, Pattern)]): Pattern =
+  runnableExamples:
+    from std/unittest import check
+    import preserves
+    check:
+      $grabRecord("Says".toSymbol, {3: grab(), 4: grab()}) ==
+        """<group <rec Says> {3: <bind <_>> 4: <bind <_>>}>"""
+  var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`rec`))
+  group.`type`.rec.label = label
+  for (i, p) in fields: group.entries[toPreserves i] = p
+  group.toPattern
 
 proc grabRecord*(label: string, fields: varargs[Pattern]): Pattern =
   ## Sugar for creating record patterns.
@@ -304,47 +269,61 @@ proc grabRecord*(label: string, fields: varargs[Pattern]): Pattern =
 
 proc grabDictionary*(bindings: sink openArray[(Value, Pattern)]): Pattern =
   ## Construct a pattern that grabs some dictionary pairs.
-  DCompoundDict(entries: bindings.toTable).toPattern
+  var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`dict`))
+  for (key, val) in bindings: group.entries[key] = val
+  group.toPattern
 
 proc grabDictionary*(bindings: sink openArray[(string, Pattern)]): Pattern =
   ## Construct a pattern that grabs some dictionary pairs.
   ## Keys are converted from strings to symbols.
-  result = DCompoundDict().toPattern
-  for (key, val) in bindings.items:
-    result.dcompound.dict.entries[key.toSymbol] = val
+  var group = PatternGroup(`type`: GroupType(orKind: GroupTypeKind.`dict`))
+  for (key, val) in bindings: group.entries[toSymbol key] = val
+  group.toPattern
 
-proc depattern(comp: DCompound; values: var seq[Value]; index: var int): Value
+proc depattern(group: PatternGroup; values: var seq[Value]; index: var int): Value
 
 proc depattern(pat: Pattern; values: var seq[Value]; index: var int): Value =
   case pat.orKind
-  of PatternKind.DDiscard:
+  of PatternKind.`discard`:
     discard
-  of PatternKind.DBind:
+  of PatternKind.`bind`:
     if index < values.len:
       result = move values[index]
       inc index
-  of PatternKind.DLit:
-    result = pat.dlit.value.toPreserves
-  of PatternKind.DCompound:
-    result = depattern(pat.dcompound, values, index)
+  of PatternKind.`lit`:
+    result = pat.`lit`.value.toPreserves
+  of PatternKind.`group`:
+    result = depattern(pat.group, values, index)
 
-proc depattern(comp: DCompound; values: var seq[Value]; index: var int): Value =
-  case comp.orKind
-  of DCompoundKind.rec:
-    result = initRecord(comp.rec.label, comp.rec.fields.len)
-    for i, f in comp.rec.fields:
-      result[i] = depattern(f, values, index)
-  of DCompoundKind.arr:
-    result = initSequence(comp.arr.items.len)
-    for i, e in comp.arr.items:
-      result[i] = depattern(e, values, index)
-  of DCompoundKind.dict:
+proc depattern(group: PatternGroup; values: var seq[Value]; index: var int): Value =
+  case group.`type`.orKind
+  of GroupTypeKind.rec:
+    result = initRecord(group.`type`.rec.label, group.entries.len)
+    var i: int
+    for key, val in group.entries:
+      if i.fromPreserves key:
+        result[i] = depattern(val, values, index)
+  of GroupTypeKind.arr:
+    result = initSequence(group.entries.len)
+    var i: int
+    for key, val in group.entries:
+      if i.fromPreserves key:
+        result[i] = depattern(val, values, index)
+  of GroupTypeKind.dict:
     result = initDictionary(Cap)
-    for key, val in comp.dict.entries:
+    for key, val in group.entries:
       result[key] = depattern(val, values, index)
 
 proc depattern*(pat: Pattern; values: sink seq[Value]): Value =
   ## Convert a `Pattern` to a `Value` while replacing binds with `values`.
+  runnableExamples:
+    from std/unittest import check
+    import preserves
+    type Foo {.preservesRecord: "foo".} = object
+      a, b: int
+    let pat = grabType Foo
+    let val = depattern(pat, @[1.toPreserves, 5.toPreserves])
+    check $val == "<foo 1 5>"
   var index: int
   depattern(pat, values, index)
 
@@ -359,44 +338,73 @@ proc fromPreservesHook*[T](lit: var Literal[T]; pr: Value): bool =
 proc toPreservesHook*[T](lit: Literal[T]): Value =
   lit.value.grab.toPreserves
 
+func isGroup(pat: Pattern): bool =
+  pat.orKind == PatternKind.`group`
+
+func isMetaDict(pat: Pattern): bool =
+  pat.orKind == PatternKind.`group` and
+    pat.group.type.orKind == GroupTypeKind.dict
+
+proc metaApply(result: var Pattern; pat: Pattern; path: openarray[Value], offset: int) =
+  if offset == path.len:
+    result = pat
+  elif result.isGroup and result.group.entries[1.toPreserves].isMetaDict:
+    if offset == path.high:
+      result.group.entries[1.toPreserves].group.entries[path[offset]] = pat
+    else:
+      metaApply(result.group.entries[1.toPreserves].group.entries[path[offset]], pat, path, succ offset)
+  else:
+    assert result.isGroup, "non-group: " & $result
+    assert result.group.entries[1.toPreserves].isMetaDict, "non-meta-dict: " & $result.group.entries[1.toPreserves]
+    raise newException(ValueError, "cannot inject into non-group pattern " & $result)
+
+proc observePattern*(pat: Pattern; injects: openarray[(seq[Value], Pattern)]): Pattern =
+  result = dropType Observe
+  var meta = pat.toPreserves.drop
+  for (path, pat) in injects:
+    metaApply(meta, pat, path, 0)
+  result.group.entries[0.toPreserves] = meta
+
 type
   Path* = seq[Value]
   Paths* = seq[Path]
   Captures* = seq[Value]
   Analysis* = tuple
+    presentPaths: Paths
     constPaths: Paths
     constValues: seq[Value]
     capturePaths: Paths
 
 func walk(result: var Analysis; path: var Path; p: Pattern)
 
-func walk(result: var Analysis; path: var Path; key: int|Value; pat: Pattern) =
-  path.add(key.toPreserves)
+func walk(result: var Analysis; path: var Path; key: Value; pat: Pattern) =
+  path.add(key)
   walk(result, path, pat)
   discard path.pop
 
 func walk(result: var Analysis; path: var Path; p: Pattern) =
   case p.orKind
-  of PatternKind.DCompound:
-    case p.dcompound.orKind
-    of DCompoundKind.rec:
-      for k, e in p.dcompound.rec.fields: walk(result, path, k, e)
-    of DCompoundKind.arr:
-       for k, e in p.dcompound.arr.items: walk(result, path, k, e)
-    of DCompoundKind.dict:
-      for k, e in p.dcompound.dict.orderedEntries: walk(result, path, k, e)
-  of PatternKind.DBind:
+  of PatternKind.group:
+    for k, v in p.group.entries: walk(result, path, k, v)
+  of PatternKind.`bind`:
     result.capturePaths.add(path)
-    walk(result, path, p.dbind.pattern)
-  of PatternKind.DDiscard: discard
-  of PatternKind.DLit:
+    walk(result, path, p.`bind`.pattern)
+  of PatternKind.`discard`:
+    result.presentPaths.add(path)
+  of PatternKind.`lit`:
     result.constPaths.add(path)
-    result.constValues.add(p.dlit.value.toPreserves)
+    result.constValues.add(p.`lit`.value.toPreserves)
 
 func analyse*(p: Pattern): Analysis =
   var path: Path
   walk(result, path, p)
 
+func checkPresence*(v: Value; present: Paths): bool =
+  result = true
+  for path in present:
+    if not result: break
+    result = step(v, path).isSome
+
 func projectPaths*(v: Value; paths: Paths): Option[Captures] =
   var res = newSeq[Value](paths.len)
   for i, path in paths:
@@ -408,30 +416,27 @@ func projectPaths*(v: Value; paths: Paths): Option[Captures] =
 proc matches*(pat: Pattern; pr: Value): bool =
   let analysis = analyse(pat)
   assert analysis.constPaths.len == analysis.constValues.len
-  for i, path in analysis.constPaths:
-    let v = step(pr, path)
-    if v.isNone: return false
-    if analysis.constValues[i] != v.get: return false
-  for path in analysis.capturePaths:
-    if isNone step(pr, path): return false
-  true
+  result = checkPresence(pr, analysis.presentPaths)
+  if result:
+    for i, path in analysis.constPaths:
+      let v = step(pr, path)
+      if v.isNone: return false
+      if analysis.constValues[i] != v.get: return false
+    for path in analysis.capturePaths:
+      if step(pr, path).isNone: return false
 
-func capture*(pat: Pattern; pr: Value): seq[Value] =
+proc capture*(pat: Pattern; pr: Value): seq[Value] =
   let analysis = analyse(pat)
   assert analysis.constPaths.len == analysis.constValues.len
-  for i, path in analysis.constPaths:
-    let v = step(pr, path)
-    if v.isNone : return @[]
-    if analysis.constValues[i] != v.get: return @[]
-  for path in analysis.capturePaths:
-    let v = step(pr, path)
-    if v.isNone: return @[]
-    result.add(get v)
+  if checkPresence(pr, analysis.presentPaths):
+    for i, path in analysis.constPaths:
+      let v = step(pr, path)
+      if v.isNone : return @[]
+      if analysis.constValues[i] != v.get: return @[]
+    for path in analysis.capturePaths:
+      let v = step(pr, path)
+      if v.isNone: return @[]
+      result.add(get v)
 
 when isMainModule:
-  let txt = readAll stdin
-  if txt != "":
-    let
-      v = parsePreserves(txt)
-      pat = grab v
-    stdout.writeLine(pat)
+  stdout.writeLine stdin.readAll.parsePreserves.grab

src/syndicate/protocols/dataspacePatterns.nim

@@ -29,58 +29,58 @@ type
         `embedded`* {.preservesEmbedded.}: EmbeddedRef
 
   
-  DLit* {.preservesRecord: "lit".} = object
-    `value`*: AnyAtom
-
-  DBind* {.preservesRecord: "bind".} = object
-    `pattern`*: Pattern
-
-  DDiscard* {.preservesRecord: "_".} = object
-  
-  DCompoundKind* {.pure.} = enum
+  GroupTypeKind* {.pure.} = enum
     `rec`, `arr`, `dict`
-  DCompoundRec* {.preservesRecord: "rec".} = object
+  GroupTypeRec* {.preservesRecord: "rec".} = object
     `label`*: Value
-    `fields`*: seq[Pattern]
 
-  DCompoundArr* {.preservesRecord: "arr".} = object
-    `items`*: seq[Pattern]
+  GroupTypeArr* {.preservesRecord: "arr".} = object
+  
+  GroupTypeDict* {.preservesRecord: "dict".} = object
+  
+  `GroupType`* {.preservesOr.} = object
+    case orKind*: GroupTypeKind
+    of GroupTypeKind.`rec`:
+        `rec`*: GroupTypeRec
 
-  DCompoundDict* {.preservesRecord: "dict".} = object
-    `entries`*: Table[Value, Pattern]
+    of GroupTypeKind.`arr`:
+        `arr`*: GroupTypeArr
 
-  `DCompound`* {.preservesOr.} = object
-    case orKind*: DCompoundKind
-    of DCompoundKind.`rec`:
-        `rec`* {.preservesEmbedded.}: DCompoundRec
-
-    of DCompoundKind.`arr`:
-        `arr`* {.preservesEmbedded.}: DCompoundArr
-
-    of DCompoundKind.`dict`:
-        `dict`* {.preservesEmbedded.}: DCompoundDict
+    of GroupTypeKind.`dict`:
+        `dict`*: GroupTypeDict
 
   
   PatternKind* {.pure.} = enum
-    `DDiscard`, `DBind`, `DLit`, `DCompound`
+    `discard`, `bind`, `lit`, `group`
+  PatternDiscard* {.preservesRecord: "_".} = object
+  
+  PatternBind* {.preservesRecord: "bind".} = object
+    `pattern`*: Pattern
+
+  PatternLit* {.preservesRecord: "lit".} = object
+    `value`*: AnyAtom
+
+  PatternGroup* {.preservesRecord: "group".} = object
+    `type`*: GroupType
+    `entries`*: Table[Value, Pattern]
+
   `Pattern`* {.acyclic, preservesOr.} = ref object
     case orKind*: PatternKind
-    of PatternKind.`DDiscard`:
-        `ddiscard`*: DDiscard
+    of PatternKind.`discard`:
+        `discard`*: PatternDiscard
 
-    of PatternKind.`DBind`:
-        `dbind`* {.preservesEmbedded.}: DBind
+    of PatternKind.`bind`:
+        `bind`* {.preservesEmbedded.}: PatternBind
 
-    of PatternKind.`DLit`:
-        `dlit`* {.preservesEmbedded.}: DLit
+    of PatternKind.`lit`:
+        `lit`* {.preservesEmbedded.}: PatternLit
 
-    of PatternKind.`DCompound`:
-        `dcompound`* {.preservesEmbedded.}: DCompound
+    of PatternKind.`group`:
+        `group`* {.preservesEmbedded.}: PatternGroup
 
   
-proc `$`*(x: AnyAtom | DLit | DBind | DDiscard | DCompound | Pattern): string =
+proc `$`*(x: AnyAtom | GroupType | Pattern): string =
   `$`(toPreserves(x))
 
-proc encode*(x: AnyAtom | DLit | DBind | DDiscard | DCompound | Pattern): seq[
-    byte] =
+proc encode*(x: AnyAtom | GroupType | Pattern): seq[byte] =
   encode(toPreserves(x))

src/syndicate/protocols/http.nim

@@ -47,7 +47,7 @@ type
   
   HttpRequest* {.preservesRecord: "http-request".} = object
     `sequenceNumber`*: BiggestInt
-    `host`*: string
+    `host`*: RequestHost
     `port`*: BiggestInt
     `method`*: Symbol
     `path`*: seq[string]
@@ -115,6 +115,17 @@ type
     `req`*: HttpRequest
     `res`* {.preservesEmbedded.}: Value
 
+  RequestHostKind* {.pure.} = enum
+    `present`, `absent`
+  `RequestHost`* {.preservesOr.} = object
+    case orKind*: RequestHostKind
+    of RequestHostKind.`present`:
+        `present`*: string
+
+    of RequestHostKind.`absent`:
+        `absent`* {.preservesLiteral: "#f".}: bool
+
+  
   PathPatternElementKind* {.pure.} = enum
     `label`, `wildcard`, `rest`
   `PathPatternElement`* {.preservesOr.} = object
@@ -149,6 +160,7 @@ proc `$`*(x: HostPattern | HttpListener | MethodPattern | MimeType | QueryValue
     HttpService |
     HttpBinding |
     HttpContext |
+    RequestHost |
     PathPatternElement |
     Chunk |
     PathPattern): string =
@@ -163,6 +175,7 @@ proc encode*(x: HostPattern | HttpListener | MethodPattern | MimeType |
     HttpService |
     HttpBinding |
     HttpContext |
+    RequestHost |
     PathPatternElement |
     Chunk |
     PathPattern): seq[byte] =

src/syndicate/protocols/noise.nim

@@ -48,6 +48,17 @@ type
         `absent`*: SecretKeyFieldAbsent
 
   
+  SessionItemKind* {.pure.} = enum
+    `Initiator`, `Packet`
+  `SessionItem`* {.preservesOr.} = object
+    case orKind*: SessionItemKind
+    of SessionItemKind.`Initiator`:
+        `initiator`* {.preservesEmbedded.}: Initiator
+
+    of SessionItemKind.`Packet`:
+        `packet`*: Packet
+
+  
   NoiseProtocolKind* {.pure.} = enum
     `present`, `invalid`, `absent`
   NoiseProtocolPresent* {.preservesDictionary.} = object
@@ -83,6 +94,9 @@ type
     `service`*: ServiceSelector
 
   ServiceSelector* = Value
+  Initiator* {.preservesRecord: "initiator".} = object
+    `initiatorSession`* {.preservesEmbedded.}: EmbeddedRef
+
   NoiseStepDetail* = ServiceSelector
   NoiseSpecKey* = seq[byte]
   NoiseSpecPreSharedKeys* = Option[Value]
@@ -105,17 +119,21 @@ type
 
   
 proc `$`*(x: NoiseDescriptionDetail | NoisePreSharedKeys | SecretKeyField |
+    SessionItem |
     NoiseProtocol |
     NoisePathStepDetail |
     NoiseServiceSpec |
+    Initiator |
     NoiseSpec |
     Packet): string =
   `$`(toPreserves(x))
 
 proc encode*(x: NoiseDescriptionDetail | NoisePreSharedKeys | SecretKeyField |
+    SessionItem |
     NoiseProtocol |
     NoisePathStepDetail |
     NoiseServiceSpec |
+    Initiator |
     NoiseSpec |
     Packet): seq[byte] =
   encode(toPreserves(x))

src/syndicate/relays.nim

@@ -251,7 +251,7 @@ proc recv(relay: Relay; buf: openarray[byte]; slice: Slice[int]) =
   var pr = decode(relay.wireBuf)
   if pr.isSome: dispatch(relay, pr.get)
 
-proc recv(relay: Relay; buf: openarray[byte]) =
+proc recv(relay: Relay; buf: openarray[byte]) {.used.} =
   feed(relay.wireBuf, buf)
   var pr = decode(relay.wireBuf)
   if pr.isSome: dispatch(relay, pr.get)
@@ -393,11 +393,12 @@ when defined(posix):
           entity.alive = false
           close(entity.sock)
       onStop(turn, kill)
-      publish(turn, ds, TransportConnection(
+      var ass = TransportConnection(
           `addr`: ta.toPreserves,
           control: newCap(entity, turn),
           resolved: entity.relay.peer.accepted,
-        ))
+        )
+      publish(turn, ds, ass)
     run(entity.relay.facet, setup)
     let buf = new seq[byte]
     entity.alive = true
@@ -549,31 +550,28 @@ proc connectRoute(turn: var Turn; ds: Cap; route: Route; transOff: int) =
   onPublish(turn, ds, acceptPat) do (origin: Cap):
     walk(turn, ds, origin, route, transOff, 0)
 
-type StepCallback = proc (turn: var Turn; step: Value; origin, next: Cap) {.closure.}
+type StepCallback = proc (turn: var Turn; step: Value; origin: Cap; res: Resolved) {.closure.}
 
 proc spawnStepResolver(turn: var Turn; ds: Cap; stepType: Value; cb: StepCallback) =
-  let stepPat = grabRecord(stepType, grab())
-  let pat = ?Observe(pattern: ResolvedPathStep?:{1: stepPat}) ?? {0: grabLit(), 1: grab()}
+  let pat = observePattern(
+      ResolvedPathStep?:{1: grabRecord(stepType)},
+      { @[0.toPreserve]: grabLit(), @[1.toPreserve]: grab() },
+    )
   during(turn, ds, pat) do (origin: Cap; stepDetail: Literal[Value]):
-    let step = toRecord(stepType, stepDetail.value)
     proc duringCallback(turn: var Turn; ass: Value; h: Handle): TurnAction =
-      var res = ass.preservesTo Resolved
-      if res.isSome:
-        if res.get.orKind == ResolvedKind.accepted and
-            res.get.accepted.responderSession of Cap:
-          cb(turn, step, origin, res.get.accepted.responderSession.Cap)
-      else:
-        publish(turn, ds, ResolvedPathStep(
-            origin: origin, pathStep: step, resolved: res.get))
+      var res: Resolved
+      if res.fromPreserves ass:
+        cb(turn, stepDetail.value, origin, res)
       proc action(turn: var Turn) =
         stop(turn)
       result = action
     publish(turn, origin, Resolve(
-        step: step, observer: newCap(turn, during(duringCallback))))
+        step: stepDetail.value, observer: newCap(turn, during(duringCallback))))
 
 proc spawnRelays*(turn: var Turn; ds: Cap) =
-  ## Spawn actors that manage routes and appeasing gatekeepers.
-  let transPat = ?Observe(pattern: !TransportConnection) ?? { 0: grab() }
+  ## Spawn actors that manage routes and appease gatekeepers.
+
+  let transPat = observePattern(!TransportConnection, { @[0.toPreserves]: grab() })
     # Use a generic pattern and type matching
     # in the during handler because it is easy.
 
@@ -600,20 +598,21 @@ proc spawnRelays*(turn: var Turn; ds: Cap) =
           resolved: rejected(embed e),
         ))
 
-  let resolvePat = ?Observe(pattern: !ResolvePath) ?? {0: grab()}
+  let resolvePat = observePattern(!ResolvePath, {@[0.toPreserves]: grab()})
   during(turn, ds, resolvePat) do (route: Literal[Route]):
     for i, transAddr in route.value.transports:
       connectRoute(turn, ds, route.value, i)
 
   spawnStepResolver(turn, ds, "ref".toSymbol) do (
-      turn: var Turn, step: Value, origin: Cap, next: Cap):
+      turn: var Turn, step: Value, origin: Cap, res: Resolved):
     publish(turn, ds, ResolvedPathStep(
-        origin: origin, pathStep: step, resolved: next.accepted))
+        origin: origin, pathStep: step, resolved: res))
 
 type BootProc* = proc (turn: var Turn; ds: Cap) {.closure.}
 
 proc resolve*(turn: var Turn; ds: Cap; route: Route; bootProc: BootProc) =
   ## Resolve `route` within `ds` and call `bootProc` with resolved capabilities.
+  let pat = ResolvePath ?: {0: ?route, 3: ?:ResolvedAccepted}
   during(turn, ds, ResolvePath ?: {0: ?route, 3: ?:ResolvedAccepted}) do (dst: Cap):
     bootProc(turn, dst)
 

src/syndicate/skeletons.nim

@@ -9,32 +9,28 @@ import ./actors, ./bags, ./patterns
 import ./protocols/dataspacePatterns
 
 type
-  DCompound = dataspacePatterns.DCompound
   Pattern = dataspacePatterns.Pattern
   Path = seq[Value]
   ClassKind = enum classNone, classRecord, classSequence, classDictionary
   Class = object
     kind: ClassKind
     label: Value
-    arity: int
 
 func classOf(v: Value): Class =
   case v.kind
-  of pkRecord: Class(kind: classRecord, label: v.label, arity: v.arity)
-  of pkSequence: Class(kind: classSequence, arity: v.len)
+  of pkRecord: Class(kind: classRecord, label: v.label)
+  of pkSequence: Class(kind: classSequence)
   of pkDictionary: Class(kind: classDictionary)
   else: Class(kind: classNone)
 
 proc classOf(p: Pattern): Class =
-  if p.orKind == PatternKind.DCompound:
-    case p.dcompound.orKind
-    of DCompoundKind.rec:
-      Class(kind: classRecord,
-        label: p.dcompound.rec.label,
-        arity: p.dcompound.rec.fields.len)
-    of DCompoundKind.arr:
-      Class(kind: classSequence, arity: p.dcompound.arr.items.len)
-    of DCompoundKind.dict:
+  if p.orKind == PatternKind.group:
+    case p.group.type.orKind
+    of GroupTypeKind.rec:
+      Class(kind: classRecord, label: p.group.`type`.rec.label)
+    of GroupTypeKind.arr:
+      Class(kind: classSequence)
+    of GroupTypeKind.dict:
       Class(kind: classDictionary)
   else:
     Class(kind: classNone)
@@ -69,13 +65,14 @@ type
   LeafProc = proc (l: Leaf; v: Value) {.closure.}
   ObserverProc = proc (turn: var Turn; group: ObserverGroup; vs: seq[Value]) {.closure.}
 
-proc getLeaves(cont: Continuation; constPaths: Paths): LeafMap =
+proc getLeaves(cont: Continuation; presentPaths, constPaths: Paths): LeafMap =
   result = cont.leafMap.getOrDefault(constPaths)
   if result.isNil:
     new result
     cont.leafMap[constPaths] = result
     assert not cont.isEmpty
     for ass in cont.cache:
+      # TODO: check presence
       let key = projectPaths(ass, constPaths)
       if key.isSome:
         var leaf = result.getOrDefault(get key)
@@ -165,25 +162,13 @@ proc getOrNew[A, B, C](t: var Table[A, TableRef[B, C]], k: A): TableRef[B, C] =
     result = newTable[B, C]()
     t[k] = result
 
-iterator pairs(dc: DCompound): (Value, Pattern) =
-  case dc.orKind
-  of DCompoundKind.rec:
-    for i, p in dc.rec.fields:
-      yield (i.toPreserves, p,)
-  of DCompoundKind.arr:
-    for i, p in dc.arr.items:
-      yield (i.toPreserves, p,)
-  of DCompoundKind.dict:
-    for pair in dc.dict.entries.pairs:
-      yield pair
-
 proc extendWalk(node: Node; popCount: Natural; stepIndex: Value; pat: Pattern; path: var Path): tuple[popCount: Natural, nextNode: Node] =
   case pat.orKind
-  of PatternKind.DDiscard, PatternKind.DLit:
+  of PatternKind.`discard`, PatternKind.lit:
     result = (popCount, node)
-  of PatternKind.DBind:
-    result = extendWalk(node, popCount, stepIndex, pat.dbind.pattern, path)
-  of PatternKind.DCompound:
+  of PatternKind.`bind`:
+    result = extendWalk(node, popCount, stepIndex, pat.`bind`.pattern, path)
+  of PatternKind.`group`:
     let
       selector: Selector = (popCount, stepIndex,)
       table = node.edges.getOrNew(selector)
@@ -198,7 +183,7 @@ proc extendWalk(node: Node; popCount: Natural; stepIndex: Value; pat: Pattern; p
         if v.isSome and class == classOf(get v):
           result.nextNode.continuation.cache.incl a
     result.popCount = 0
-    for step, p in pat.dcompound.pairs:
+    for step, p in pat.group.entries:
       add(path, step)
       result = extendWalk(result.nextNode, result.popCount, step, p, path)
       discard pop(path)
@@ -231,7 +216,7 @@ proc add*(index: var Index; turn: var Turn; pattern: Pattern; observer: Cap) =
   let
     cont = index.root.extend(pattern)
     analysis = analyse pattern
-    constValMap = cont.getLeaves(analysis.constPaths)
+    constValMap = cont.getLeaves(analysis.presentPaths, analysis.constPaths)
     leaf = constValMap.getLeaf(analysis.constValues)
     endpoints = leaf.getEndpoints(analysis.capturePaths)
   # TODO if endpoints.cachedCaptures.len > 0:

syndicate.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version = "20240408"
+version = "20240421"
 author        = "Emery Hemingway"
 description   = "Syndicated actors for conversational concurrency"
 license       = "Unlicense"

tests/test_patterns.nim

@@ -1,103 +1,87 @@
 # SPDX-FileCopyrightText: ☭ Emery Hemingway
 # SPDX-License-Identifier: Unlicense
 
-import std/[options, tables, unittest]
+import std/[options, sequtils, tables, unittest]
 
-import preserves, syndicate, syndicate/protocols/gatekeeper
+import preserves, syndicate, syndicate/protocols/[gatekeeper, timer]
 
 import ./test_schema
 
-test "patterns":
-  let
-    pat = ?Observe(pattern: !Foo) ?? {0: grab()}
-    text = """<rec Observe [<rec rec [<lit foo> <arr [<bind <_>> <_> <_>]>]> <_>]>"""
-  check($pat == text)
+suite "example":
+  var pat: Pattern
+  check pat.fromPreserves parsePreserves"""
+      <group <arr> {
+        0: <lit 1>
+        1: <bind <group <arr> {
+          0: <bind <_>>
+          1: <_>
+        }>>
+        2: <_>
+      }>
+    """
 
-  let
-    worte = @["alles", "in", "ordnung"]
-    observer = Observe(pattern: inject(?:Foo, { 0: ?worte })).toPreserves
-    have = capture(pat, observer).toPreserves.unpackLiterals
-    want = [worte.toPreserves].toPreserves
-  check(have ==  want)
+  const A = "[1 2 3]"
+  test A:
+    let v = parsePreserves A
+    check:
+      not pat.matches(v)
 
-type Obj {.preservesDictionary.} = object
-  a, b, c: int
-
-test "dictionaries":
-  let pat = ?:Obj
-  var source = initDictionary(Cap)
-  source["b".toSymbol] = 2.toPreserves
-  source["c".toSymbol] = 3.toPreserves
-  source["a".toSymbol] = 1.toPreserves
-
-  let values = capture(pat, source)
-  check values.len == 3
-  check values[0] == 1.toPreserves
-  check values[1] == 2.toPreserves
-  check values[2] == 3.toPreserves
-
-type
-  File {.preservesDictionary.} = object
-    name: string
-    path: string
-    size: BiggestInt
-    `type`: string
-  Files = Table[Symbol, File]
-  Fields = Table[Symbol, string]
-
-  Request {.preservesRecord: "request".} = object
-    seq: BiggestInt
-    fields: Fields
-    files: Files
-
-test "literals":
-  const txt = """<rec request [<lit 3> <dict {artists: <lit "kyyyyym"> date: <lit "2023-10-14"> notes: <lit "Lots of stuff"> title: <lit "Domes show">}> <dict {front-cover: <dict {name: <lit "ADULT_TIME_Glielmi.jpg"> path: <lit "/tmp/652adad1b3d2b666dcc8d857.jpg"> size: <lit 255614> type: <lit "image/jpeg">}>}>]>"""
-  var pr = parsePreserves(txt)
-
-  var capture: Literal[Request]
-  check capture.fromPreserves(pr)
-
-suite "captures":
-  for txt in [
-      "#f",
-      "#t",
-      "0",
-      "-1",
-      "foo",
-      "<foo>",
-      "[0, 1, 2]",
-      ]:
-    test txt:
-      let
-        pr = parsePreserves txt
-        pat = grab pr
-      checkpoint $pat
-      check pat.matches pr
-
-suite "protocol":
-  test "Observe":
-    let pat = ?:Observe
-    const text = """<rec Observe [<bind <_>> <bind <_>>]>"""
-    check $pat == text
-
-  test "later-than":
+  const B = "[1 [2 3] 4]"
+  test B:
     let
-      obsA = parsePreserves"""<Observe <rec later-than [<lit 1704113731.419243>]> #f>"""
-      obsB = parsePreserves"""<Observe <rec Observe [<rec rec [<lit later-than> <arr [<rec lit [<bind <_>>]>]>]> <_>]> #f>"""
-      patA = """<rec later-than [<lit 1704113731.419243>]>""".parsePreserves.preservesTo(Pattern).get
-      patB = """<rec Observe [<rec rec [<lit later-than> <arr [<rec lit [<bind <_>>]>]>]> <_>]>""".parsePreserves.preservesTo(Pattern).get
+      v = parsePreserves B
+      c = parsePreserves "[[2 3] 2]"
+    check pat.matches(v)
+    check pat.capture(v).toPreserves == c
 
-      patC = grab obsA
+  const C = "[1 [2] 5]"
+  test C:
+    let v = parsePreserves C
+    check:
+      not pat.matches(v)
 
-    test $patC:
-      check patC.matches obsA
-
-    test $patB:
-      checkpoint $obsA
-      check patB.matches obsA
-
-  test "TransportConnection":
+  const D = "[1 [2 3 4] 5]"
+  test D:
     let
-      pat = TransportConnection ?: { 2: ?:Rejected}
-      text = """<rec connect-transport [<_> <_> <rec rejected [<bind <_>>]>]>"""
-    check $pat == text
+      v = parsePreserves D
+      c = parsePreserves "[[2 3 4] 2]"
+    check pat.matches(v)
+    check pat.capture(v).toPreserves == c
+
+  const E = "[1 [<x> <y>] []]"
+  test E:
+    let
+      v = parsePreserves E
+      c = parsePreserves "[[<x> <y>] <x>]"
+    check pat.matches(v)
+    check pat.capture(v).toPreserves == c
+
+suite "meta":
+
+  test "pattern-of-pattern":
+    let
+      pat = grabRecord("foo".toSymbol, {666: drop()})
+      meta = pat.toPreserves.drop()
+    check $meta == "<group <rec group> {0: <group <rec rec> {0: <lit foo>}> 1: <group <dict> {666: <_>}>}>"
+
+  test "observe":
+    let
+      val = Observe(pattern: LaterThan ?: {0: drop 12.24}).toPreserves
+      pat = grab(val)
+    check pat.matches(val)
+    check pat.capture(val) == @[val]
+    let
+      meta = observePattern(!LaterThan, {@[0.toPreserves]: grabLit()})
+      res = parsePreserves "[12.24]"
+    check meta.matches(val)
+    check meta.capture(val).toPreserves == res
+
+  test "connect-transport":
+    let pat = parsePreserves"""
+        <group <rec connect-transport> {0: <group <rec unix> {0: <lit "/run/user/1000/dataspace">}> 2: <group <rec accepted> {0: <bind <_>>}>}>
+      """.preservesTo(Pattern).get
+    let val = parsePreserves"""
+        <connect-transport <unix "/run/user/1000/dataspace"> #:#f <accepted #:#f>>
+      """
+    check pat.matches(val)
+    check pat.capture(val).toPreserves == parsePreserves "[#:#f]"

tests/test_timers.nim

@@ -2,7 +2,9 @@
 # SPDX-License-Identifier: Unlicense
 
 import std/times
-import syndicate, syndicate/drivers/timers
+import syndicate, syndicate/drivers/timers, preserves
+
+var passCount = 0
 
 runActor("timer-test") do (turn: var Turn):
   let timers = newDataspace(turn)
@@ -10,13 +12,21 @@ runActor("timer-test") do (turn: var Turn):
 
   onPublish(turn, timers, ?LaterThan(seconds: 1356100000)):
     echo "now in 13th bʼakʼtun"
+    inc passCount
 
   after(turn, timers, initDuration(seconds = 3)) do (turn: var Turn):
     echo "third timer expired"
-    stopActor(turn)
+    assert passCount == 3
+    inc passCount
 
   after(turn, timers, initDuration(seconds = 1)) do (turn: var Turn):
     echo "first timer expired"
+    assert passCount == 1
+    inc passCount
 
   after(turn, timers, initDuration(seconds = 2)) do (turn: var Turn):
     echo "second timer expired"
+    assert passCount == 2
+    inc passCount
+
+doAssert passCount == 4, $passCount